Lathe



P. BOILLAT May l2, 1944.

LATI-IE Filed 001'.. 24, 1940 3 Sqheets-Sheet 1 May Z, 1944.

P. BolLLAT LATHE Filed Oc'l'.. 24, 1940 s sheets-sheet 2 A @WM/1M NWN uRN Sm.

gm. mmm, Em. f 55).

Patented May 2, 1944 LATHEV Philippe Boillat, Tavennes, Switzerland,assgnor to the firm Tavennes Machine Co.

Tavennes, Switzerland, a joint-stock company of Switzerland ApplicationOctober 24, 1940, Serial No. 362,665 In Great Britain October 30, 1939 3Claims.

This invention relates to lathes, specially to automatic lathes. Itshows a special arrangement of the tools, particularly, but notexclusively, of the radially working tools.

In the types of lathes hitherto known the radially working tools werearranged in boxes ofthe star type, i. e., all the tools were placed insuch a way, that the point of intersection of their axes lay on the axisof the work piece. Owing to this arrangement, the number of tools waslimited.

In a lathe according to my invention these disadvantages are eliminated.

An object of my invention is to provide a slidably and pivotally mountedtool carrier which is formed as a sector. This allows the provision of apractically unlimited number of tools per sector. The change of thetools can be elected in the shortest time possible, whereby the socalleddead time is reduced to a minimum. Not only is the constructionsimplified but the eilciency of the lathe is also highly increased.

Another Objectis to provide suitable driving means for swinging thesector in order to change the too-ls and other driving means forimparting a feed motion to the sector. These driving means may bemembersand means carrying a cam path or may be eccentricsl A further object Yisto provide an intermittently driven'member for imparting a tool-changingrotation to said sector and a continuously driven means for imparting afeed motion to the sector. The continuously driven means may be a camdisc mounted on a continuously drivenV shaft which, furthermore, carriesa controlling means for controlling a disengaging coupling operatingsaid intermittently driven member.

Other objects and features will be apparent as the following descriptionproceeds, reference being had to the accompanying drawings in which,

Fig. l is` a front view of the device, partly in section; f

Fig.' 2 is a top viewof the device, partly in section,

' Fig. 3 is a section through one sector,

Fig. 4 is a front View of the other sector,

Fig. 5 is a top view of the sector shown in Fig. 4, v Y

Figs. 6 and '7 are side views of the levers for imparting a feed motionto the sectors;r

' Fig. 8 is a side view of the cam disc'and the lever driving the leversshown in Figs. 6 and 7 Fig. 9 is a section taken on line IXQIX of Fig.1, showing parts 'of the drive for the toolchanging motion of onesector, the references in parentheses indicating the corresponding partsof the drive of the other sector.

Fig. 10 is a section taken on line X-X of Fig. 2;

Fig. 1l is a developed projection of the teeth of the coupling, engagingone another.

Fig. 12 shows a plate carrying an inclined surface of the disengagingcoupling.

Fig. 13 shows a lever of the coupling controlling means, seen in thedirection of arrrow L in Fig. 2. v

Fig. 14 is a section taken `on line XIV-XIV of Fig. 2.

The radially working tools 200 to 205 are fixed to the sectors 200 and201. The fixing of these tools to the sectors is shown in Figs. 3, 4 and5. Each of the sectors comprises a recess 208 from which elevations 209rise. Adjusting screws 2|0 are screwed to these elevations. Betweenthese adjusting screws and the Wedges 2|| the tools 200 to 205 areplaced. These wedges can be pressed between the tools and the elevationsby means of the bolts 2|2 screwed through the portion 2|3 of thesectors. In this way the tools can be clamped to the sectors.

'I'he sectors 203, 201 are pivotally mounted on the forked ends 2|4, 2|5of the rods 2|6, 2|1 by means of the pivots 2|3, 2|9. The rods 216, 2|'lare mounted, with allowance for sliding, on the bearings 220, 22|. Thesectors are guided, on both sides, by guide surfaces 222, 223respectively. The surfaces 222 are provided on ledges 224 screwed to theframe 6 and the surfaces 223 on the shields 220 of the frame. Springs22T-located in holes 228l of the frame and attached to extensions 229 ofthe pivots 2|8 and 2|9 tend to return the tools from the work piece 230.,The feed motion is imparted to the tools by rocking levers 23|, 232pivotally 'mounted on bearings 233 (Figs. l, 6 and 7) by means of`pivots 234. These levers 23|, 232 have shoes 235 pivotally attached toone end of said levers andv engaging correspondinghshoes 236 on theVrods 2|6,.'2|'|. The levers 23| 'and 232 are connected with'each otherby means'of rod 231. On the pivot 234'of lever 23| an arm 238 ismounted. Thisl arm isV connected by means of a rod 302 with a' rockinglever 239 (Figs. 2 and 8) pivotally mounted on a bracket 240 attachedtov the frame 6.? To'this lever 239 a pin 24| or a rollerisfixedcooperating with a' cam `disc 242mounted on' aF shaft 003v placed onbearings 304`of`the frame 6 (Fig. 8). Shaft 603 is continuously drivenata speed which 265, 266. Pin 259 is held in continuous contactV withthe cam 26| by the weight of the sector 201 and its accessories. Inorder to provide for continuous contact between Din 258 and cam 260`levers 3|3, 3|4 are pivotally mounted by means of a shaft 3|5. A rod 3|6connects lever 3|4 with the sector 206 and a spring 3|1 connects lever3|3 with the frame 6. From Fig. lit may be seen that the spring 3|1constantly` presses pin 258 against the cam 2 60. Shaft 264 is adaptedto move intermittently. The intermittent rtation may be obtained by thefollowing mechanism: Helical gear 269 mounted on shaft 264 mesheshelical gear v21) whose shaft 21| is journaled on the bearings 212 and213. The o-ne half 214 of a toothed coupling is slidably attached to theshaft 21| by means of a key 215. The other half 216 o-f the coupling isXed to the shaft 211 journaled on the bearings 218. Shaft l1211 carriesgear wheel 219 meshing gear wheel 288 on the shaft 44 to which aconstant speed is transmitted from a motor not shown by insertion ofgearings not shown. Each half of the coupling has a toothed rimcomprising teeth 282, 28,3 respectively, cooperating with one another(Fig. 11) when the coupling is thrownl in. A collar 284 is threaded tothe shaft 21| and a spring 285 is provided between collar 284 and half214, tending to throw the teeth 282 and 283 into gear with oneV anotherby shifting the half 214. Two platesv 286 with an inclined surface 281(Figs. and 12) are screwed to the half 212. VThe upper face of theseplates 286 comprising the surface 281 is adapted to cooperate with thestop 288 forminggone end of the rod 289 mounted, with allowance forsliding, on the bearing 290.

To this. rod 289 the forked end 29| of the rockinglever 292 is pivotallyfixed by means of a bolt 29,3 (Figs. 2 and 13). Lever 292 is mounted onvthe shaft 29,4' journaled on bearings 295 of the frame. The other end296 ofthe rocking lever 292l is adapted to cooperate with a driver 291attached to the disc 298 mounted on the shaft 603. A spring 299connecting an arm 360- attached to lever- 292` with a stationary point30| of the machine is provided to keep the stop 288m engaging position.In order to prevent the end 296 of the lever 292 from being constantlypressed against the disc 298 a washer 306. is secured to the rod 289limiting the motion of this rod and thus of'lever 29,2.

is pressed into the hollows 3|2 by means of the spring 3| suffices tostop shaft 21 The action of the mechanism described is as follows: Whentwo of the tools 200 to 205 for instance, tools 20| and 204 have beenbrought into the position shown in Figure 1 cam disc 242 gives thesetools a feed motion towards the center of the work piece 230 by means ofthe lever 239, rod 302, lever 23|, rod 231 and lever 232. When theadvance of the tools is finished and the pin 24| has attained thesmallest radius of the cam disc 242, i. e., when the springs 221 havewithdrawn the tools, the driver 291 on disc 29.8, swings lever 292against the elfect of spring 299, stop 288 disengages the one plate 286,so that the teeth 282 of the half 214, under the effect of spring 285,engage the teeth 283 of the half 216. The cylinders 262, 263 with thecams 260, 26| are now rotated and the sectors 206, 201 rapidly swungaround their pivots 2|8, 2| 9 by means of the rods 246, 241 until othertools, for instance, 200 and 205 are brought into operating position.When the latter is reached, the other plate 286 rotating with thecoupling half 214 knocks with its inclined surface 281 against stop 288and, by further rotation, spring 285 is compressed and the teeth of thehalf 214 are put out ofv gear with the teeth of half 216 and the-cylinders 262, 263 stopped with 'the help of the stopping device shownin Figs. 2 and 14. Half 212 has made half a revolution. Now the advanceof the other tools 200 and 205 can begin.

The cam 'disc 242 illustrated in Fig. 2 has only one cam. It, therefore,imparts per revolution a forward motion to only two tools lying oppositeeach other. The sectors 206, 201 must, therefore, be turned only onceper each revolution of disc 242. Thus only one driver 291 must beprovidedr on disc 298. Be it, however, presumed that, e. g., all thetools 200 to 205 should work during one revolution of disc 242, thenthree cams should be provided on said disc'242 and, therefore, threedrivers 291 on disc 298.

The sectors 206, 201 may also be driven independent of one another byseparate cam discs,

' and the camsl on these cam discs may be arranged in such a way thatonly one tool at a f time works. If, in this case, all the tools shouldIn, order to stop the rotation of the shaft 2.64,

when the teeth'of the coupling are disengaged, a cam disc 3.0.1 (Figs. 2and 14) is fixed to shaft 21|. This. cam disc cooperatesk with the pinor roller 308. attached to the one end of the rocking lever 309 mountedon shaft. 310. Spring 9|-| fixed to the frame. 6; and to. the other endof the lever 309 presses pinl .308 against the cam disc` 30:1. Ihehollows 3|2- ofY the cam disc 301 correspond to the position K of thestop 238 shown,A in TEig. 12J* 11,1, this position the teeth aredisengaged pressure., with which pin 36,3

work during one revolution of the cam discs six drivers ought to beprovided on disc 298.

Preferably the cams260, 26|V are interchangeably mounted on thecylinders 282, 2.63, e. g. by screwing them to the cylinders. Theconstruction of the cams suitable for each machining desired and theprovision of their mutual position on the cylinders is well known tothose skilled in the art and, therefore, need not be described.

It is understood that the invention is not limited to the described andillustrated embodiment. The'number of the tools may vary at will, andmany changes, both with regard to the arrangement of the toolsv on theirsupports and to the motion-transmitting means may be resorted to bythose skilled in the art without departingfrom the principle oftheinvention. Furthermore, the invention canV also be appliedto axiallyworking tools.

WhatI claimisy l. In an automatic lathe, a spindle to hold the workpiece', a sector, a plurality of radially working tools. fixed to saidsector to be alternately brought in and out of working position,'adjustable means mounting sad sector to rotate about an axis lying aplane goingthrough the axis Q f said spindle and through the cuttingedge of that of said tools which is in Working position, a rotatablemember mounted to oscillate said sector, suitable motion-transmittingmeans fastened to said sector and in cooperation with said rotatablemember, a rotatable means, and other suitable motion-transmitting meansbetween said rotatable means and said adjustable mounting means toimpart feed motion to said sector.

2. In an automatic lathe, ,a spindle to hold the work piece, a sector, aplurality of radially Working tools fixed to said sector to bealternately brought in and out of working position, said sector beingmounted rotatably about an axis lying in a plane going through the axisof said spindle and through the cutting edge of that of the tools whichis in working position, a rotatable member comprising a cam path shapedto oscillate said sector, motion transmitting means including elementsin cooperation with said cam path, a rod pivotally .attached to saidelements and to said sector, a rotatable means carrying another cam pathto impart a feed motion to said sector',

and other suitable motion-transmitting means between said other cam pathand said sector.

3. In an automatic lathe, a spindle to hold the work piece, a bearing, arod slidably mounted on said bearing, a sector, a plurality of radiallyworking tools fixed to said sector to be alternately brought in and outof working position, said sector being rotatably xed to the end of saidrod about an axis lying in a plane going through the axis of saidspindle and through the cutting edge of that of the tools which is inWorking position, a rotatable member comprising a cam path shaped tooscillate said sector, motion-transmitting means including elements incooperation with said cam path, another rod pivotally attached to saidelements and to said sector, .a rotatable means carrying another campath to impart a feed motion to said sector, and other suitable motiontransmitting means between said other cam path and said rod.

PHILIPPE BOILLAT.

